Self-loading mechanism for a scraper

ABSTRACT

Movement of earth over the cutting edge of a scraper is assisted by a pair of blades which orbit around an axis above the cutting edge, the blades being maintained in an upright orientation throughout the orbit. To hold the blades in the fixed orientation with a minimum of structural complication, the blades are fastened to links which are connected between two eccentric rotary elements that revolve about spaced apart axes at one side of the blades.

United States Patent Knell et a1. 1451 Dec. 19, 1972 [5 1 SELF-LOADING MECHANISM FOR A 2,393,823 1/1946 SChOOiel ..198/212 x SCRAPER 2,807,377 9/1957 Pellat-Finet ..19s/212 x 3,574,960 4/1971 Peterson et al..... ..37/4 Inventors: Harvey 191M; James 3,486,251 12/1969 Carston ..37/4 Olthoff, South Netherlands; Barry 2,994,139 8/1961 Carston ..37/l26 R A. Scoggin, Plainfield; Roger M. Smith Joliet, all Of L FOREIGN PATENTS OR APPLICATIONS [73] Assignee: Caterpillar Tractor Co., Peoria, lll 485,073 12/1917 France ..37/93 Filed: y 1 1970 Primary Examiner-Robert E. Pulfrey 21 A 1' No: 55 465 Assistant Examiner-R. T. Rader 1 pp Attorney-Fryer, Tjensvold, Feix, Phillips and Lempio [52] US. Cl. ..37/4, 37/126 R, 37/129 R, [57] ABSTRACT 198/212 I Movement of earth over the cutting edge of a scraper [51] Int. Cl. ..B60p 1/00 is assisted by a pair of blades which orbit around an [58] Field of Search ..37/4, 124, 125, 126, 129; 198/10 12 212, 74/68 86 ax s above the cutting edge, the blades bemg ma ntained in an upright orientation throughout the orbit. [56 R f d To hold the blades in the fixed orientation with a 1 e erences minimum of structural complication, the blades are UNITED STATES PATENTS fastened to links which are connected between W0 60- centnc rotary elements that revolve about spaced 1,300,299 4/1919 Schlueter ..37/93 apart axes at one side of the blades 2,844,892 7/1958 Carston 1.37/4 2,201,959 5/1940 Schmidt ..l98/2l2 X 6 Claims, 5 Drawing Figures lo I7 7 4' h k I 18 t 6 p 9 l6 l PATENTED 19 I973 3. 7'06, 143

sum 1 0F 4 INVENTORS HARVEY A. KNELL JAMES A. OLTHOFF BARRY A. SCOGGIN BY ROGER M. SMITH W ATTORNES PATENTEU DEC 1 9 I972 SHEET 2 OF 4 INVENTORS KNELL OLTHOFF BARRY A. SCOGGIN ROGER M. SMITH f r HARVEY A. JAMES A.

BY w,

ATTORNEYS PATENTEDHE 1 1912 3,706. 143 SHEU 3 OF 4 vENToRs HARVEY A. KNELL JAMES A. LTHOFF BARRY A. scoccm ROGER M. SMITH BY 7 2 2 1 ,l'qT-goRNEys PATENTEU nzc 19 I972 SHEET 4 0F 4 INVENTORS HARVEY A. KNELL JAMES A, OLTHOFF BARRY A. SCOGGIN ROGER M. SMITH #M ATTORNEYS SELF-LOADING MECHANISM FOR A SCRAPER BACKGROUND OF THE INVENTION This invention relates to scrapers for moving earth or the like and more particularly to powered self-loading mechanisms for assisting the movement of earth into the bowl of a scraper.

Scrapers which have a .load carrying bowl with an earth cutting edge along an open face often cannot be fully loaded by relying solely on the forward motion provided by the tractiv'e unit of the scraper. The weight of the material loaded during the initial portion of the loading cycle tends to resist the entrance of additional material. This problem is widely recognized in the earth moving equipment industry and a variety of mechanisms have been developed for assisting the movement of material over the cutting .edge and into I the bowl. These include, for example, the use of supplimentary pusher tractors during the final phases of the loading cycle, the providing of additional engines for supplementary driving of the scraper wheels during loading and various forms of self-loading mechanism situated above the cutting edge to force material back into the bowl. The self-loading mechanisms variously may be chain and flight v elevators, manipulatable aprons which simulate the action of a hoe to draw material into the bowl and paddle wheel like structures having orbiting blades which perform a similar function.

As heretofore constructed or practiced, these mechanisms and techniques do not provide a fully satisfactory solution to the problem of loading scrapers under difficult working conditions. The use of pusher tractors is an obviously costly technique requiring additional personnel and additional major items of equipment at the work site. Elevators, while widely used, provide only an undesirably small increase in the capacity of the scraper and are prone. to malfunction and are often not feasible where large rocks'or other objects are present in the material tobe loaded. Orbiting blade loading mechanisms as heretofore designed have required complex, heavy and costly support and drive structure to realize the complicated pattern of movement Of the blades.

In general, it is widely recognized that more efficient, reliable and less costly means are needed for the purpose of assisting loading of scrapers.

SUMMARY OF THE INVENTION The present invention provides a compact, efficient, reliable and economically manufactured mechanism for supporting and driving orbiting blades above the cutting edge of a scraper wherein the orbiting blades are maintained at a substantially constant inclination throughout the orbiting motion. These objectives are realized by providing a pair of eccentric rotary elements at least at one side of the scraper, the elements being rotatable about spaced apart parallel axes and being coupled by links to which the orbiting blades are fastened. The eccentric rotary elements are driven by powered means whereby the blades are caused to orbit in the desired manner while the'pivoting of the links relative to the rotary elements maintains a substantially constant blade inclination throughout the orbital motion.

Accordingly, it is an object of this invention to provide for more effective and economical loading of scrapers.

It is another object of this invention to provide a loading assistmechanism for a scraper providing a forcible positive loading action with a minimum of structural complication and cost and which is highly durable and reliable in operation.

The invention together with further objects and advantages thereof will best be understood by reference to the following description of a preferred embodiment in conjunction with the accompanying drawings.

DESCRIPTION OF THE DRAWINGS In the accompanying drawings:

FIG. 1 is a side elevation view of a scraper having a portion of the bowl side wall broken out to expose selfloading mechanism in accordance with the invention;

FIG. 2 is a plan view of a portion of the scraper of FIG. 1 further illustrating the self-,loadingmechanism, portions of the structure being broken out;

' FIG. 3 is a section view taken along line III-III of FIG. 2; I

FIG. 4 is a broken out view taken along line IV--lV of FIG. 2; and

FIG. 5 is a section view taken along line V--V of FIG. 4 further clarifying certain detailsof the self-loading mechanism.

DESCRIPTION OF A PREFERRED EMBODIMENT Referring now to the drawing and particularly to FIG. 1 thereof, there is shown a scraper 11 which may be of essentially conventional construction aside from the loading assist mechanism to be hereinafter described. Thus, salient elements of the scraper 11 include an earth carrying bowl I2 havinga forward end supported by a two wheel tractor unit 13 through a draft frame 14 including draft arms 16. The back end of bowl 12 is supported by rear wheels 17 through a rear frame 18. Raising and lowering of the bowl '12 is provided for by lift jacks 19 coupled between draft frame 14 and the forward end of the bowl. The front end of the bowl 12 has an opening 21 for receiving earth and a cutting edge 22 is disposed along the lower edge .of the opening to excavate a superficial layer of earth as the bowl is drawn forward by tractor 13.

For the reasons previously discussed, forward motion of the scraper Il alone will frequently achieve only a partial loading of the bowl 12. To assure use of the full capacity of the scraper, self-loading mechanism 23 is disposed within the forward portion of the bowl to forcibly drive earth back over cutting edge 22 and up into the bowl. This action is effected by a pair of loading blades 24 and 24 which orbit around a support shaft 26 situated above cutting edge 22 in parallel relationship therewith, the blades being maintained in a substantially upright orientation throughout the orbital I motion.

Referring now to FIGS. 2 and 3 in conjunction, the loading blades 24 and 2 4' are carried on the forward end of a pair of arms 27 and 28 which are pivotably fastened to the inner side of opposite side walls 29 of bowl 12, the arms being coupled to the side walls by pivot connections 31 situated at the top of the side walls and slightly forward from cutting edge 22. Each arm 27 and 28 extends rearwardly and downward from pivot connections 31 to the region above the cutting edge. To provide for adjustment of the height of the orbit of blades 24, each arm 27 and 28 has a crankarm 32 and a hydraulic jack 33 is connected between the crankarm and a bracket 34 on the top of the bowl side wall 29 whereby extension of the jacks pivots the lower ends of arms 27 and 28 upward and contraction of the jack lowers the arms. To rigidly couple the arms 27 and 28 together, a transverse brace member 36 extends between the arms just below the pivot connectors 31.

To support the blades 24 on arms 27 and 28, the previously described shaft 26 extends between the lower ends of the arms 27 and 28, and is rotatable with respect to the arms. To provide for driving the shaft 26, with reference to FIGS. 2 and 4, arm-28 is of a thick hollow construction and a drive gear 37 is disposed coaxially on the shaft within the hollow arm. A fluid driven motor 38, coupled to a speed reduction unit 39, is secured to arm 28' in coaxial relationship with the pivot connection 31 thereof and has an output gear 41 within arm 28 whichis coupled to gear 37 by a drive chain 42 within the arm. This motor 38 rotates the blade support shaft 26.

As best shown in FIG. 1,a member 43 is-secure'd to shaft 26 at the end adjacent arm 27 and extends in opposite directions from the shaft to support one end of each of the loading blades 24 and 24. As best shown in FlG. 2, each blade 24 and 24 has a short axle 44 projecting midway between the upper and lower edges of the blade which extends into member 43 to fasten the blade thereto while providing for blade rotationrelative to member 43. Referring again to FIGS. 2 and 3 in conjunction, an additional blade support member 47 is secured to drive shaft 26 at a position near arm 28 and also has oppositely extending portions 47 which receive axle pins 44 of blades 24 and 24?. Unlike the opposite blade support member 43, member 47 has a third radially projecting portion 47" directed substantially at right angles to the portions'47 which support blades 44.

The inside surface of arm 28 is provided with a circular bearing support 48 having a center, indicated by a dashed cross 53 in FIG. 3, which is spaced from the axis of drive shaft 26 in an upward direction whereby the bearing support is eccentric relative to the drive shaft. An annular blade orientation control element 54 is disposed coaxially on bearing support 48 and journalled thereon by suitable bearing means 56 for rotation about center 53. Blade control element 54 has three radial extensions 57 spaced angularly about center 53 in a manner corresponding to the angular spacing of portions 47 and 47" of blade support member 47 with respect to the axis of drive shaft 26. One of three links 58 connects each projection 57 with the corresponding one of the portions 47' and 47" of blade support member 47, the connections of the links 58 with the elements 57, 47', and 47" being pivot joints 59. The links 58 have an effective length (i.e., the spacing between pivot joints 59) which is equal to the vertica l spacing of center 53 from the axis of drive shaft 26. Under this condition, the links 58 are constrained to maintain a constant orientation asblade support member 47 and blade orientation control element 54 revolve about their respective centers of rotation. Ac-

cordingly, as best shown in FIG. 5, the loading blades 24 and 24 may similarly be maintained in a constant orientation in the course of the orbital motion by ridgedly coupling each blade 24 and 24 to a link 58. For this purpose, the blade axles 44 extend through blade support member 47, to function as elements of pivot connections 59, and are fixedly secured to the associated link 58.

In operation, motor 38 acts through gears 41 and 37 and drive chain 42 to revolve drive shaft 26 thereby causing blade support members 47 and 43 to orbit the blades 24 and 24' around the drive shaft. The rotary motion of blade support member 47 causes links 58 to revolve blade control element 54 about the eccentric center of rotation 53 and this forces a continuous rotation of the blades 24 and 24' about the axis of axles 44 to maintain the loading blades in the preferred constant orientation throughout the orbital motion.

It will be apparent that variations in the structure are possible without departing from the substance of the invention. For example, if it is desired to reduce bending stresses on the loading blades 24, the blade orienting elements such as bearing support 48, blade control element 54 and links 58, may be duplicated at the opposite side of the blades.

What is claimed is:

1. In combination with a scraper vehicle having a bowl for receiving and transporting earth, said bowl having a cutting edge over which a surface layer of earth passes to enter said bowl, mechanism for assisting loading comprising: 1

support means disposed above said cutting edge for revolution about a first axis which is parallel thereto, said support means having a rotatable shaft co-axial with said first axis and a member which extends radially relative to said first axis; a loading blade joumalled to said radially extending member of said support means for revolution about a second axis which is parallel to said first axis and spaced therefrom and which orbits around said first axis as said support means revolves therearound; blade orientation control element mounted for rotation about a third axis which is spaced from both said first and second axes and which is parallel thereto; link connected between said radially extending member of said support means and said blade orientation control element and being pivotable with respect to each thereof whereby said control element is revolved about said third axis as said support means member revolves about said first axis and said link maintains a predetermined orientation throughout said motion, and means fastening said blade to said link whereby said blade maintains a predetermined orientation while orbiting around said first axis; said support means further including arms locating said support means in said bowl, and pivoted to said bowl, one of said arms being hollow and containing therein drive means, one end of which is operatively connected to said rotatable shaft, and another end thereof operatively connected to motor means, which is co-axial with the pivot of said hollow arm.

2 The combination defined in claim 1 wherein said support means is comprised of a rotatable shaft extending along said first axis of rotation and having one of said radially extending members at each side of said blade for receiving said blade therebetween.

3. The combination defined in claim 2 wherein said rotatable shaft is journalled in non-rotary elements at each side of said bowl and wherein one of said non-rotary elements has a circular bearing support thereon which is coaxial with said third axis and wherein said blade orientation control element is annular and journalled on said bearing support in coaxial relation thereon.

4. In a scraper which has a bowl with an edge over which material is passed to enter said bowl, loading mechanism comprising:

a pair or arms each being pivoted to an opposite side of said bowl and extendlng toward the region over said edge;

a rotatable shaft extending between said pair of arms in parallel relationship to said edge;

support means at each end of said rotatable shaft each having radially extending members;

a pair of loading blades disposed on opposite sides of said shaft between said radially extending members of said support means, each of said blades being journalled to said radially extending members of said support means for rotation relative thereto;

an annular blade orientation control element rotatably supported by one of said arms for rotation about an axis which is spaced from the axis of said shaft;

a pair of pivotable links each being connected between said blade orientation control element and said radially extending members of said support means whereby said control element is revolved around said axis of rotation thereof upon revolution of said support means about the axis of said rotatable shaft, said links having an effective length corresponding to the spacing between said axis of rotation of said control element and the axis of said shaft whereby said links maintain a constant orientation while orbiting around said shaft, said pair of links being angularly spaced 180 apart with respect to the axis of said shaft and wherein a third pivotable link is connected between said blade orientation control element and said radially extending member of said support means at a position angularly spaced substantially from each of the other links; and

means coupling each of said pair of links to an associated one of said loading blades whereby said blade is maintained at a constant orientation while orbiting around said shaft;

one of said arms being hollow and containing therein drive means, one of which is operatively connected to said rotatable shaft, and another end thereof operatively connected to motor means, said motor means being co-axial with the pivot of said hollow arm 5. The combination defined in claim 4 wherein said blade orientation control element and said links are disposed at the sides of said blades adjacent said hollow d The combination defined in claim 5 wherein said blades have axles extending from each side thereof which are receivedin said radially extending members of said support means for rotatably supporting said blades thereon and wherein said means fastening said blades to said links comprises portions of said axles which extend through said support means members and are secured to said links. 

1. In combination with a scraper vehicle having a bowl for receiving and transporting earth, said bowl having a cutting edge over which a surface layer of earth passes to enter said bowl, mechanism for assisting loading comprising: support means disposed above said cutting edge for revolution about a first axis which is parallel thereto, said support means having a rotatable shaft co-axial with said first axis and a member which extends radially relative to said first axis; a loading blade journalled to said radially extending member of said support means for revolution about a second axis which is parallel to said first axis and spaced therefrom and which orbits around said first axis as said support means revolves therearound; a blade orientation control element mounted for rotation about a third axis which is spaced from both said first and second axes and which is parallel thereto; a link connected between said radially extending member of said support means and said blade orientation control element and being pivotable with respect to each thereof whereby said control element is revolved about said third axis as said support means member revolves about said first axis and said link maintains a predetermined orientation throughout said motion, and means fastening said blade to said link whereby said blade maintains a predetermined orientation while orbiting around said first axis; said support means further including arms locating said support means in said bowl, and pivoted to said bowl, one of said arms being hollow and containing therein drive means, one end of which is operatively connected to said rotatable shaft, and another end thereof operatively connected to motor means, which is co-axial with the pivot of said hollow arm. CM,2Ombination defined in claim 1 wherein said support means is comprised of a rotatable shaft extending along said first axis of rotation and having one of said radially extending members at each side of said blade for receiving said blade therebetween.
 3. The combination defined in claim 2 wherein said rotatable shaft is journalled in non-rotary elements at each side of said bowl and wherein one of said non-rotary elements has a circular bearing support thereon which is coaxial with said third axis and wherein said blade orientation control element is annular and journalled on said bearing support in coaxial relation thereon.
 4. In a scraper which has a bowl with an edge over which material is passed to enter said bowl, loading mechanism comprising: a pair or arms each being pivoted to an opposite side of said bowl and extendIng toward the region over said edge; a rotatable shaft extending between said pair of arms in parallel relationship to said edge; support means at each end of said rotatable shaft each having radially extending members; a pair of loading blades disposed on opposite sides of said shaft between said radially extending members of said support means, each of said blades being journalled to said radially extending members of said support means for rotation relative thereto; an annular blade orientation control element rotatably supported by one of said arms for rotation about an axis which is spaced from the axis of said shaft; a pair of pivotable links each being connected between said blade orientation control element and said radially extending members of said support means whereby said control element is revolved around said axis of rotation thereof upon revolution of said support means about the axis of said rotatable shaft, said links having an effective length corresponding to the Spacing between said axis of rotation of said control element and the axis of said shaft whereby said links maintain a constant orientation while orbiting around said shaft, said pair of links being angularly spaced 180* apart with respect to the axis of said shaft and wherein a third pivotable link is connected between said blade orientation control element and said radially extending member of said support means at a position angularly spaced substantially 90* from each of the other links; and means coupling each of said pair of links to an associated one of said loading blades whereby said blade is maintained at a constant orientation while orbiting around said shaft; one of said arms being hollow and containing therein drive means, one of which is operatively connected to said rotatable shaft, and another end thereof operatively connected to motor means, said motor means being co-axial with the pivot of said hollow arm.
 5. The combination defined in claim 4 wherein said blade orientation control element and said links are disposed at the sides of said blades adjacent said hollow arm.
 6. The combination defined in claim 5 wherein said blades have axles extending from each side thereof which are received in said radially extending members of said support means for rotatably supporting said blades thereon and wherein said means fastening said blades to said links comprises portions of said axles which extend through said support means members and are secured to said links. 